Smart subs from local firms coming to the rescue

Some scientists say we know more about the surface of the moon than we do about the ocean floors of our own planet.

Three local firms — Hydroid in Bourne, Bluefin Robotics in Quincy, and OpenWater Power in Somerville — are all doing things to change that with remote-controlled vehicles cruising below the surface of the ocean. But they aren’t just mapping the depths.

Recently, a robotic submarine made by Bluefin was dispatched to the Indian Ocean in the search for the missing Malaysia Flight 370.

The local firms working with automated underwater vehicles are growing as demand for their technology increases from oil and gas companies, the Department of Defense, and ocean-exploration organizations.

“The trust and confidence in unmanned vehicle systems is really growing,” said Duane Fotheringham, president of Hydroid, now owned by Kongsberg Maritime of Norway.

Hydroid, which makes three types of underwater vehicles, broke ground on a new 40,000-square-foot facility in Bourne last year. The company employs 130 and plans to add 30 more people after the new facility opens in August.

Bluefin, a spinoff from the Massachusetts Institute of Technology, last year purchased Seebyte Ltd., a Scottish maker of software for underwater robots. The acquisition brings Bluefin’s total number of employees to 200.

“We really have a nexus of undersea robotics here in Boston,” said David Kelly, chief executive of Bluefin Robotics. “It’s an incredibly exciting time for those of us in this technology field.”

OpenWater Power, another MIT spinoff, received $450,000 in funding from the Navy last year to design fuel-cell technology that harnesses and extracts energy from aluminum in water. Its technology could one day be used to vastly increase the power of energy-storage systems for underwater vehicles.

“The Boston area has really become a mecca for underwater technology research,” said Tom Milnes, cofounder and chief executive of OpenWater Power.